(Applicant's Abstract) The Morphology Core will provide technical expertise, assistance and equipment to those investigators who wish to analyze their experiments using microscopic and morphometric techniques. Expertise and assistance will be provided by core personnel in the following areas: (1) routine light microscopy and histochemical analysis, (2) enzyme histochemistry, (3) immunohistochemistry, (4) in situ hybridization histochemistry, (5) autoradiography, (6) photomicroscopy, (7) electron microscopy, (8) confocal microscopy, (9) computer-assisted image analysis, and (10) morphometry. In addition, the Morphology Core will facilitate the acquisition, processing and storage of experimental and control tissues; maintain standards and quality control for histochemical procedures; and assist in the development of new techniques as needed. The Morphology Core will also be responsible for immunohistochemical and in situ hybridization analyses of human biopsy and autopsy material related to neonatal respiratory distress syndrome pulmonary alveolar proteinosis, hyaline membrane disease, bronchopulmonary dysplasia, interstitial lung disease, emphysema, and pulmonary malformations. The overall goal of these clinical studies will be to characterize and identify mechanisms that cause idiopathic lung disease and developmental abnormalities.